Observability of thermal effects in the Casimir interaction from graphene-coated substrates

TL;DR

This paper calculates the thermal effects on the Casimir interaction involving graphene-coated substrates, showing significant impacts for dielectric materials and potential observability in experiments with increased film thickness.

Contribution

It introduces a theoretical calculation of thermal effects in the Casimir force involving graphene coatings, highlighting conditions for experimental observation.

Findings

Graphene coating does not affect metal-metal Casimir interactions.

Graphene significantly impacts dielectric-dielectric Casimir interactions.

Thermal correction can be observed with increased film thickness.

Abstract

Using the recently proposed theory, we calculate thermal effect in the Casimir interaction from graphene-coated metallic and dielectric substrates. The cases when only one or both of the two parallel plates are coated with graphene are considered. It is shown that the graphene coating does not influence the Casimir interaction between metals, but produces large impact for dielectrics. This impact increases with decreasing static dielectric permittivity of the plate material. The thermal correction to the gradient of the Casimir force between an Au sphere and graphene coated fused silica plate is calculated. It is shown to be significanlty greater than the total experimental error in the recently performed experiment, which is demonstrated to be only one step away from observation of the thermal effect from a graphene-coated substrate at short separation distances. To achieve this goal, one should increase the thickness of the fused silica film from 300 nm to 2000 nm.